CN1647098A - Device for determining the age of a person in vehicle by measuring pupil size - Google Patents

Abstract

Disclosed is a device for determining physical data, which is characterized suitable for determining the age. A sensor is used for recording said physiological data. The device is configured particularly for measuring pupil size, which is a good parameter for distinguishing age. Preferably, said parameter is correlated with additional measured values in order to have a solid basis for determining the age.

Description

Device for recording physiological data of at least one person in a motor vehicle

Background technique

The invention relates to a device for recording physiological data of at least one occupant of a motor vehicle according to the independent claims.

The advantages of the present invention

An advantage of the recording device according to the invention in which at least one occupant is physiological data with the features described in the independent claim is that the device can determine the age of the at least one occupant by means of the physiological data. In this way, in particular retraction devices such as airbags and seat belt pretensioners can be individually activated. Since human bones become brittle in old age, in the event of a crash it is preferable to inflate the airbags less when an elderly person is detected than when a young person is detected. People over the age of 50 have only 30% of the bone toughness of people over the age of 25. Elderly occupants risk rib fractures and internal bleeding if the belt force limiter is not engaged immediately when the belt pretensioner is released.

In addition to being used in motor vehicles, the device according to the invention can also be used, for example, for age-based entry permits or age-based distribution of consumer goods.

But device of the present invention can bring into play its maximum advantage when being used in automobile especially.

The device for recording psychological data of at least one occupant as stated in the independent claim can be advantageously improved by means of the measures and solutions presented in the respective dependent claims.

It is particularly advantageous if at least one sensor for recording psychometric data is designed as a video signal generator. Preferably a video sensor is used here, in particular a stereo video sensor, which by means of triangulation can determine the distance of the person from the airbag cover, in particular the pupil size. For this purpose, the video signal generator or video sensor is equipped with an evaluation unit to measure the pupil size. From the pupil size the age of the person can be deduced in a simple manner. It is well known that pupil size decreases with age. Pupil size in older adults can drop to one third of that in younger adults.

Instead of a stereo video sensor, other methods can also be used which combine a video sensor with distance measurement. To measure distance. Other methods of triangulation are available, e.g. by patterned illumination or time-lapse methods such as LIDAR (Light Detection and Ranging), LIDAR for image transmission, radar or ultrasound or interferometry, i.e. the distance is measured using the phase shift of two laser beams It is realized through their different optical transmission paths.

The device according to the invention can advantageously combine the video signal generator with other sensors in order to obtain other data for the adaptation of the pullback device to the specific situation, or to correlate the pupil size with other physiological data, so that the age determination can be based on a further good basis. For this purpose, for example, hair color and/or facial smoothness and/or skin texture can be analyzed from image signals, in particular video signals. It is also possible to train a classifier with the aid of image signals to classify persons into different age groups.

Measurements alone may give a false impression of a person's age, but combined with correlations, especially with pupil size, these parameters make age determination more reliable.

Pulse frequencies determined by means of pressure sensors or electrical parameters such as skin resistance or capacitive measurements for determining body moisture can be used as further measured values. Water in the body also expresses different ages of a person, as the water in the elderly drops to 60% of body weight, compared to 90% in young children.

Furthermore, the device of the invention advantageously uses measurements taken from a person's body weight to infer the person's age. Body weight measurements can be determined with seat cushions or force rods or other sensors.

Description of drawings

Exemplary embodiments of the invention are shown in the drawings and described in detail below.

Fig. 1 represents the block diagram of device of the present invention;

Fig. 2 shows the device of the present invention arranged in a car.

Detailed ways

In particular due to the introduction of the front passenger airbag, for reasons of safety and insurance technology it is necessary to identify the passenger seat occupied by a person. In the event of an accident and the passenger seat is not occupied, there is no passenger to protect that seat, so if the airbag deploys, it means unnecessarily high repair costs. For this purpose, seat occupancy recognition is widely used in order to recognize a person. There are also approaches to automatic child seat recognition.

According to the invention, it becomes possible to configure the physiological data recording device to determine the age of the passenger, ie the occupant of the vehicle. However, the device according to the invention can also be used outside the car, but in the car the age can be determined in the event of an accident, so that the retracting device can be activated depending on the situation and the person.

In particular, the evaluation of the pupil size of the occupant by means of a video signal generator, for example a video system, and the combination of this information with other independent measured values can determine the age of the occupant. Especially since pupil size decreases significantly with age, it is a good parameter to identify older people. The table below shows the decrease in pupillary cross-section with age.

Table 1 Pupil diameter of people of different ages age) Daytime (mm) Night (mm) Difference (mm) 20 4.7 8.0 3.3 30 4.3 7.0 2.7 40 3.9 6.0 2.1 50 3.5 5.0 1.5 60 3.1 4.1 1.0 70 2.7 3.2 0.5 80 2.3 2.5 0.2

In this way, in the event of a motor vehicle accident, according to the invention, targeted protection of elderly people can be achieved. This type of protection for the elderly is much more important than sex recognition, since for example non-pregnant women can tolerate higher accelerations and pressures per unit area than men of the same age and therefore require airbag protection only at higher crash speeds.

In particular, with the aid of a stereoscopic video system, the distance of the passenger to the airbag cover and the pupil size of the person can be determined by triangulation. Alternatively, a video camera combined with an ultrasonic distance sensor can be used to measure pupil size. In both cases, it is crucial to have a video system aimed at the person's eye, which is tracked and measured at regular intervals. size. The brightness of the vehicle can be estimated using known parts of the vehicle, for example the roof of the vehicle. Age estimation is possible with the help of brightness in the car and pupil size. Temporal filtering improves the reliability of this age estimate compared to short-term fluctuations in brightness. For a person who wears glasses, although there is distortion, if for example the size of the eye and iris is used as a reference, the size of the pupil can be determined fairly accurately, or the eye distortion can be calculated back.

The device according to the invention can be used to its greatest advantage if the measurement of the pupil size for age estimation is combined with other measured values in order thereby to obtain a redundancy and greater certainty security. These additional measurements such as hair color, facial skin wrinkles, under-eye circles or skin texture can come from the same video system, but they can also come from other sensor systems, where for example pressure can be used in the steering wheel rim A sensor measures the pulse of a car driver. The pulse of the elderly is slower than that of the young. Piezoelectric sensors can also be used as pressure sensors, such sensors being arranged, for example, in the seat.

The characteristic determination of the driver's hands can be carried out on the steering wheel rim by measuring the electrical resistance, ie the skin resistance, temperature and pressure distribution over a certain distance, eg 2 centimeters, by means of sensors. At least one indication of the age of the person can also be obtained from this.

Another possibility is to detect displacement currents in an electric field, ie to detect the capacitance between the transmitting and receiving electrodes in the seat. In the case of passenger identification, for example with video systems, the water content of the human body can be deduced from capacitive measurements. A small capacitance in the electric field means less moisture and thus indicates an elderly person, since the moisture of an elderly person is generally only 60% compared to the 90% moisture of a child.

Using a video system for determining the size of the occupant and an absolute weight-sensitive system, for example with a force rod in the seat height adjustment joint or between the seat rail and the seat rocker arm, the ratio of the occupant's weight to the size can be determined. If this ratio falls below a limit value, a further indication of the elderly is given.

But the measurement of pupil size is the most important basis for determining age. Of course, the pupils can be unusually dilated for many hours by the action of the drug, as can be confirmed, for example, by a retinal examination by an ophthalmologist. Pupil measurements alone can therefore lead to erroneous results and thus undesired adverse consequences for elderly passengers when the passenger protection system is activated in the event of a crash.

Therefore for a reliable anthropometric non-invasive age determination, data from the other sensors listed above, or parts thereof, must be taken into account.

FIG. 1 shows a block diagram of the device according to the invention. A video signal generator 1 is connected to an evaluation unit 2 via a data output. The evaluation unit 2 is connected to a second data input of a controller 3 which has a processor. A weight sensor 6 is connected to the second data input of the controller 3, which determines the weight of a passenger on the seat, referred to here as a load cell, which is arranged in the seat height adjustment joint. The controller 3 is used to control the pullback device, so the controller 3 is connected to the pullback device 4 through a data output terminal. The controller 3 is connected via a third data input to a crash sensor 5 in order to detect a crash. In the sensor device 5, besides the inertial sensor, there is also a pre-crash sensor or a deformation sensor. In addition to the weight sensor 6, which can be designed as a cushion, there are also other sensors, for example sensors for recording a person's pulse or electrical sensors for determining the impedance or capacitance of the person's skin. The video signal generator 1 is designed here as a stereoscopic video sensor, so that the pupil size of the person and the distance from the airbag protective layer are measured by triangulation. These tasks are carried out by the evaluation unit 2, which is designed here as a microcontroller. The analysis unit 2 can also be arranged in the controller 3 , for example also only as software of the central processing unit of the controller 3 .

By means of the video signal generator 1 and optionally the above-mentioned further sensors, the controller 3 can then determine the age of the occupant concerned. In the case of a collision accident, the controller 3 can control the relevant airbags or seat belt tensioners according to the age of the occupant according to this determined age.

Fig. 2 shows the device of the present invention arranged in an automobile. The same elements are still provided with the same reference numerals. Video signal generator 1 is connected via a data output to evaluation unit 2 , which in turn is connected to a first data input of controller 3 . A weight sensor 7 is connected to the second data input of the controller 3 , the weight sensor is located in the seat cushion 9 of the car seat, and a pressure sensor 8 is connected to the third data input of the controller 3 . This pressure sensor is used to measure the pulse of the driver sitting in the seat. A pressure sensor 12 is connected to the fourth data input of the controller 3 in order to measure the driver's pulse at the steering wheel 11 here. In addition, an impedance measuring device 13 is arranged in the steering wheel 11 , which is connected to the fifth data input of the controller 3 for determining the impedance of the skin. Other types of sensors mentioned above can also be used here. Fewer sensors than shown here may also be used. It is also possible to place the sensor in the backrest 10 of the seat. In particular, only one ultrasonic distance measuring device can also be used here.

Claims (11)

1. write down the device of at least one individual's physiological data, this device has at least one and is used for the sensor (1,6,7,8,12,13) of recording said physiological data, this device is configuration like this, and promptly this device was determined by means of the age that physiological data can carry out at least one individual.

2. by the device of claim 1, it is characterized by, at least one sensor (1,6,7,8,12,13) is a flying-spot video generator.

3. press the device of claim 2, it is characterized by, this flying-spot video generator (1) is a three-dimensional video-frequency sensor, this video sensor (1) configuration analytic unit (2), this analytic unit is used for measuring the pupil size, and wherein this device is determined the age with the pupil size.

4. by the device of claim 3, it is characterized by, video sensor (1) is used for implementing triangulation.

5. by each device of claim 2 to 4, it is characterized by, except flying-spot video generator (1), be provided with a ultrasonic distance sensor and measure the distance of at least one individual to the air bag protective seam.

6. by the device of claim 3, it is characterized by, this device construction becomes to make the measurement of pupil size and another measured value is relevant to determine the age at least.

7. by the device of claim 6, it is characterized by, the tissue conduct of this device usefulness hair color and/or face smoothness and/or skin is another measured value at least.

8. by claim 6 or 7 device, it is characterized by, this device is with at least one individual's pulse conduct another measured value at least, and is provided with a pressure transducer (3) and measures pulse.

9. by the device of claim 8, it is characterized by, pressure transducer (8,12) is arranged in steering wheel (11) or the automotive seat (9).

10. by each device of claim 6 to 9, it is characterized by, in order to measure another measured value at least, this device is determined at least one individual's a electrical quantity.

11. by each device of claim 6 to 10, it is characterized by, in order to measure another measured value at least, this device has disposed at least one individual's body weight determination device.

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